Originally Posted by metallo

How were the seats "opened up?" Did they actually displace other passengers? Was this J or Y?

I'm curious because I just had space opened for myself and a companion on a flight recently. We needed to be re-accommodated, and there was only one seat on the new flight (but two of us), so they oversold the flight for my companion and advised me the gate agent would be able to see the "oversell list" so they weren't sure how the gate would handle that, but it was a confirmed new reservation with a seat assignment, and there were no issues with checking in or during boarding. I'm not sure, though, whether someone was booted, given a voucher for taking a flight the next day, etc.